It's like shifting from Romero to Carpenter. Everyone physically mutating in nauseating Old God's abominations would be wonderfully horrific.

About Ny'alotha, the name to me sounds like a lexical reference to this, but I belive that the effective nature of it is a more substantial reference to Cthulhu's city, which is underwater (like this Ny'alotha) so is indeed some sort of Old God's city for me, N'zoth's one probably.

Nyarlathotep is also mentioned in "The Rats in the Walls" as a faceless god in the caverns of earth's center.

Finally, in "The Haunter of the Dark" (1936), the nocturnal tentacled, bat-winged monster dwelling in the steeple of the Starry Wisdom sect's church is identified as another form, or manifestation of, Nyarlathotep.

I'd say Ny'alotha is under the sea. I wouldn't be suprised if it is Naz'jatar tbh, and that the Black Forest is metaphorical for something. I doubt its actually a forest, and theres a chance that the stuff we've heard about Ny'alotha already is metaphorical.

That's a pretty small head he has then if he is really the size of northrend o.O i know his prison at least reaches Vordrassil to gnaw on it roots, but it doesn't mean he is as big as his prison.

Don't forget the bit where Old Gods aren't exactly... 100% material. While tendrils of Yogg-Saron did indeed reach as far as Vordrassil and Azjol'Nerub, it might very well be that those were simply the places where he could reach through the cracks in his prison.

His blood is found throughout Northrend, but that could just indicate that it flows from a source throughout the land. Or possibly the deposits of his blood come from his battle with the Titans that presumably took place somewhere in the region of Northrend, and he shed a lot of blood all over the place. The faceless ones and forgotten ones are certainly found everywhere.

His influence is also spread through his blood, so that may go some distance towards explaining his influence stretching so far from his prison.

Honestly, I've heard the assertion that the Old Gods are absolutely gigantic, but I don't see any great sign of it. If they're around the size of the forgotten ones I'd agree, that's pretty big. Certainly mountain-sized.

Far beneath the oceans is a dark wretched dry (repeat, DRY which means no swimming) continent called Ny'alotha where N'Zoth dwells. In theory it's a massive underground cavern, but it's so large that you can never tell that it is one for it's so massive, it has an atmosphere. The skylines of Ny'alotha are similar to Outland in the regard that there are no blue skies and sun. Thick fog with giant crystals, mists from massive chunks of ice, and the fading light from the ocean above create seemingly natural skylines while other zones are influenced by the presence of N'Zoth, from pulsing clouds to shifting caverns to corrupted mists.

On this continent lies a variety of zones, such as:

The Sunken City of Ny'alotha - Probably based on "R'lyeh", the sunken city where C'thulu sleeps. Lot of madness going on. Similar to Azeroth, it's the name of both the continent and a kingdom.

The Black Forest - "Look around... They will all betray you... Flee screaming into the black forest..." and "There is a little lamb lost in dark woods...".

Naz'Jatar - Where Queen Azshara reigns. Deathwing's Cataclysm damaged it but it still stands as the Naga capital. Remember, N'Zoth did save Azshara and her Highborne.

Then you have room for all sorts of stuff, like ice caverns, volcanic lands, Old God affected dry sea floors, salt flats, etc.

All that information is from a book released in ~2001 that has since been removed from Warcraft canon: so it's not that.

Based on the quotes, the best fit is: Ny'alotha is a sunken city, in which an old god sleeps. This is undoubtedly Nazjatar, which is inside the Rift (The Dark Below). N'zoth is also currently resting next to Nazjatar: we have seen numerous hints at N'zoth already.

There is also been hints at The Emerald Dream - in one of the Malfurion books he encounters a rift in the emerald dream which is often speculated (even by Malfurion, i think?) to be The Rift. N'zoth is also the creator of the Emerald Dream, so if he's sleeping in the Rift, and Malfurion believes the origin of the ED is the Rift of Aln (The Rift as seen from within the Emerald Dream), then he's probably seeing the nexus between N'zoths Azerothian mind (at The Rift) as it is portrayed within the ED (as The Rift of Aln).

I'm confident it's a Nazjatar / N'zoth / Emerald Dream expansion.

The only canon references to The Dark Below in WoW right now are the following:

Ozumat, Fiend of the Dark Below (who was born in Gishan Caverns, in The Rift).

Erudax, The Duke of Below - agent of N'zoth

Both of those are the only canon references, and both of them link directly back to N'zoth (either because Gishan Caverns is right beside N'zoths current bed, or because Erudax is an emissary of N'zoth).

Yogg Saron has been hinting at N'zoth since Northrend, Cataclysm was N'zoths doing, Pandaria was Y'shaarj trying to get ready to combat N'zoth waking up (which we foil), and then during the final Siege of Orgrimmar battle Y'shaarj warns us about N'zoth.

That's a pretty small head he has then if he is really the size of northrend o.O i know his prison at least reaches Vordrassil to gnaw on it roots, but it doesn't mean he is as big as his prison.

This thing with Vordrassil is probably a remain of the Old Location intended for Yogg, Yogg was actually supposed to be in Azjol-Nerub being BFF's with the Nerubians, in Vordrassil there is even some kind of Entrance that could easily be turned into a Instance Entrance.

I think that Old Gods are big, but not that big that their size spans entire continents.

Too often, we are mistaken for druidic types. perhaps that's true for some shaman, but do not let yourself be plagued by the ignorant belief that we are always peaceful.
Nothing about what I do is harmonious. I command the elements to my will. There is nothing offered in return. I would have it no other way.

I am liking the idea from that "leak" that Ny'alotha is actually N'zoth himself.

As somebody have already stated in this thread, many of Lovecraft's themes dealt with shapeless, formless, abstract beings that cannot be fully grasped. We do not know how OGs actually look like as we only encountered parts of them, but those parts were quite material, even if aberrant in shape.

However N'zoth is essentially a "dream lord", so I think it would be fitting if N'zoth's true form would be something more abstract than C'thun's or Yogg-saron's form.

I would imagine Nazjatar would be somewhere near Ny'alotha but not the same as it, then as we descend further into the rift, there would be a twisted city in the middle of it, littered with towering spires and architecture that seems both inorganic and fleshy at the same time, and this would be N'zoth's "appearance" in Azeroth. And perhaps in the middle would be a larger spire where the Emerald Dream bleeds through and that spire leads to a further part of the city that gets more surreal and demented, as it is essentially in the Nightmare. That would be a raid and N'zoth's dreamlike manifestation would be in it.

This thing with Vordrassil is probably a remain of the Old Location intended for Yogg, Yogg was actually supposed to be in Azjol-Nerub being BFF's with the Nerubians, in Vordrassil there is even some kind of Entrance that could easily be turned into a Instance Entrance.

I think that Old Gods are big, but not that big that their size spans entire continents.

I'm leaning towards the idea that Ny'alotha and N'Zoth are one in the same. This would be a prime time to reveal the true extent of an Old God's corporeal form. A lot of people seem skeptical of the idea that Old Gods are gigantic.. but a close reading of the lore reveals that they are truly massive in actual proportion, easily the size of a continent like Pandaria. What we fight as "surface forms" are a mere fraction of their total power.

The Old Gods were buried by the Titans, and a magical slumber was induced on them (this suppresses the vast majority of their power, but not all of it). The continents that they reside under serve as their primary prisons, while secondary prisons house 3 of them in their surface forms (Yogg'Saron, Y'Shaarj, and the 5th Unnamed). It is stated that 3 Old Gods were imprisoned in this way, while two of them got away. C'Thun was the first to get away (he was thought dead by the Titans when they killed his surface form during the start of the war), and N'Zoth is the other.

The 5th one is likely beneath Kharazan, and is alluded to with the statement about the "Rook among the dead trees". Deadwind Pass. Kharazan Tower (looks like a Rook in Chess). It was stated a long time ago that there was a sub-level of Kharazan. This is probably the last Titan Prison.

Think of the Old Gods as gigantic parasites. Even when the Titans arrived, the level of infestation on Azeroth had reached critical levels. Excising them would destroy the world. So they imprisoned them instead. But a lot of people are confused by what the prisons are.. as above, let me repeat, there are two kinds of prisons that were used. The "Watcher Prison", like Yogg'Saron and Y'Shaarj, and the "Tectonic Prison", the continents that cover their main bodies and suppress the vast majority of their power. The Watcher Prisons are for preventing situations like what happened with C'Thun, where he sprang up basically out of nowhere. It is difficult to combat an enemy that presents an unpredictable situation.. whereas Watcher Prisons keep a close eye on the Old Gods and prevent them from freely interacting (obviously, corruption being a large problem still).

So.. N'Zoth was never imprisoned in a WATCHER PRISON style, but he was still put into a magical slumber, and buried beneath Azeroth. The only reason he exists under an ocean is because of The Sundering. But his capital, his city, Ny'alotha, is probably within a large cavernous zone.

Think about what the Cataclysm was trying to accomplish. That spell would have fractured Azeroth, destroyed the World Pillar, causing massive devastation when that realm collided, particularly above the Maelstrom (which is above N'Zoth's domain). This would have destroyed his "tectonic prison", releasing his main body and allowing him to finally unleash his true powers. That was the entire purpose of the spell. Not to destroy Azeroth, but to free N'Zoth (and presumably the other Old Gods after or during, depending on the level of destruction we're talking about).

I think people on these forums vastly underestimate just how powerful and enormous the Old Gods really are, because what we've seen so far of them in-game has been tiny vestiges of power lying within Watcher Prisons. I really hope the Dark Below will put that to rest. It's time for a full Old God reveal.